The A- and B-band resonance Raman spectra of Cu(II)-bisacetylacetone in methanol solution were obtained and their intensity patterns were found to be significantly different. It appears that the A- band structural dynamics is mostly along the photophysically and photochemically important C gamma C beta/C beta C alpha and Cu-O stretch reaction coordinates, while the B-band structural dynamics is mainly along photochemically important Cu-O stretch reaction coordinate. The significantly different structural dynamics provide an evident that the primary photoreduction reactions of Cu(II)-bisacetylacetone are wavelength dependence. (C) 2010 Elsevier B.V. All rights reserved.